Apparatus for sheathing cores



Dec. 12, 1933.

G. L. CHERRY 1,939,041 APPARATUS FOR SHEATHING CORBS Uriginal FiledApril '6, 1929 Q YT Q q} h b: V

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Q. L..CHERRY y \R'Y M ATTORNEY Patented Dec. 12, 1933 1,939,041

APPARATUS FOR SHEATHING COBES George L. Cherry, La Grange, Ill.,assignor to Western Electric Company, Incorporated, New York, N. Y., acorporation of New York Original application April 6, 1929, Serial No.353,042. Divided and this application May 16, 1930. Serial No. 452,855

10 Claims. (01. 18-13) This invention relatestoapparatus for sheathchinewithout removing the exhausted reel. ing cores, and more particularly toapparatus for From the extrusion head, the newly coated wires extrudinga plastic covering upon cores in strand are passed to a chamber 16,where steam or other form, and is a division of my Patent No. 1,823,885,heating medium is admitted thereto through an dated September 22, 1931.inlet 1'7, the heating medium being maintained An object of theinvention is to provide a simple, under pressure in the chamber. Fromchamber inexpensive and efficient apparatus for sheathing 16 the coatedand heat treated wires pass cores. through a substantially steam-tightseal 18, and

In accordance with one embodiment of the inthence over a capstan 19 to atake-up reel 20. vention, there is provided in an apparatus for Thecapstan 19 is driven, by means not shown, at 65 applying a vulcanizedrubber covering upon one a predetermined speed which is coordinated withor more wires or conductors, an extrusion head the extruding speed ofthe extrusion head 9. for extruding the covering material upon The seal18 comprises a threaded cap 21 which the wires and a heated chamber for11- holds apertured discs 22, of rubber or other resili- 1 canizing thecovering. The extrusion head is ent material, against the end of thesteam chamconstructed and designed so as to insure the her 16. A hollowcylindrical retaining member proper locating and positioning of afloating eX- 25 holds the discs 22 in yielding contact with the trusiondie and a cooperating core tube assembly coated wires 11 and 12 movingtherethrough, to therein. The extrusion die communicates with preventleakage of the steam from the chamber. the vulcanizing chamber throughan apertured The retaining member 25 is held in position by 75 entranceplate and an aperture in the extrusion a bell-crank lever 26 which isyieldingly urged head block. The die is yieldingly urged toward againstthe retaining member by means of a pissthe plate by the pressure of thecovering material ton 27 mounted in a cylinder 28 and actuated by beingextruded, whereby the die cooperates with compressed air or otherpressure medium adthe plate and a gasket interposed therebetween mittedthrough duct 29, the piston being yield- 80 to provide a seal betweenthe die and the vulcaningly urged upwardly by a coiled spring 24. izingchamber. The rear or entrance end of chamber 16 con- It is believed thata complete understanding nects, through a head block 30 (Fig. 2), with aof the invention will be had from the following tapered entrance member31 which bears against detailed description, reference being had to thea floating coating or extrusion die 32 of the insu- 85 ying drawing,wherein lating head 9, a gasket 34, preferably of asbestos Fig. 1 is adiagrammatic elevational view, fibre saturated with graphite, or of softcopper, partly in section, of one form of core sheathing aluminum, orother suitable gasket material, beapparatus embodying the features ofthe'invening interposed between the entrance member and t the die toprevent leakage of steam. A steam- 90 Fig. 2 is an enlarged fragmentarysection on tight seal between the die and the chamber 16 line 2-2 ofFig. 1; is thereby maintained during the operation of Fig. 3 is adetailed view of the core tube asthe machine by reason of the die beingpressed sembly; forwardly against the entrance member by the ofconductors coated by the apparatus shown therethrough by a conveyingscrew 33. The in Figs. 1 and 2; and floating die 32 has at its inner enda throat 101 Fig. 5 is a similar view showing a modified form with aconical shaped opening which communiof the same. cates with a smallaperture 102 having the ulti- Referring now to the drawing wherein likemate configuration of the outer surface of the 100 reference numeralsdesignate corresponding parts covered wires 10 and 11. throughout theseveral views, the reference nu- The core tube assembly (Fig. 3)comprises a meral 9 designates the extrusion head of an apmember or coretube holder 35 having a concave paratus adapted to apply a commoncoating of surface 54 to deflect the insulating material torubbercompound or other material 10 to wires ward die 32, and having a centralpartition mem- 105 11 and 12 which pass therethrough from supply ber 36adapted to divide the stream of insulating reels 13, 14 and 15, thesupply reels being so material into two portions and thereby evenlymounted with respect to the extrusion machine distribute the pressurethereof. A pair of core that when one reel becomes exhausted the wiretubes 37 are fixedly mounted within member 36, from another reel may bethreaded into the maextending forwardly therefrom, and are shaped Fig. 4is an enlarged sectional view of a pair pressure of the coating material10 being forced die '32 to form thereon a common insulating covering,which covering is preferably shaped to indicate polarity, by means ofspaced, longitudinally extending fins 45 as shown in Fig. 4, or by meansof a flattened surface 46, as shown in Fig. 5. As shown in Fig. 2 thecore tubes 37 extend forward into the throat 101 of the die 32 to thepoint at which the throat 101 joins the aperture 102. At this point inthe die the covering material 10 is moving therethrough at approximatelythe same rate of speed as it moves through the outer end of the die.This makes it possible to insert a new length of wire through either ofthe core tubes 37 to a point where the insulating material 10 will grabthe end of the new wire and carry it through the die at approximatelythe same speed as the completed product is propelled by the capstan 19.When the relation of the ends of the core tubes 37 and throat 101 is asshown it becomes unnecessary to stop the operation of the machine eachtime one of the spools of wire 13 or 14 becomes exhausted. Members 32and 35 are slidably mounted in a cylindrical opening or bore 38 formedin a die holding block 39 of the extrusion head, a stop or aligningplate 40 being fixed in the bore to coact with lugs 41 and 42 on themembers 32 and 35 to limit their inward movement. Block 39 has acylindrical outer surface except at opposite faces 43 and 44 which areformed plane in order to align the block 39 accurately within the block30. The die holding block 39 constructed as shown and above describedhas two flat faces 43 and 44 parallel to each other, and two teretefaces between the flat faces 43 and 44, all of which are in contact withcorresponding inner surfaces of the block 30. The die holding block 39has another pair of fiat faces 48 and 49 which are perpendicular to theflat faces 43 and 44. A flange or externally threaded nut 50 is threadedinto the head block 30 of the extrusion head 9 and bears against thefiat face 49 of the die holding block 39 to securely hold the block 39in its proper position. In order to prevent the parts from beingincorrectly assembled, the face 43 is made slightly smaller than theface 44, as indicated in Fig. 1, while the opposite ends of stop 40 arespaced at different distances from surfaces 43 and 44, respectively, asindicated in Fig. 2. It will thus be seen that the block 39 cannot beinserted within block 30 except in a predetermined position, and that itcannot be so inserted when members 32 and 35 are improperly positionedtherein.

While the invention hasbeen described with particular reference to anapparatus for extruding and vulcanizing a common covering upon a pair ofwires, it will be readily understood that it may be applied withsuitable modifications to apparatus for sheathing a single wire as wellas more than two wires, and that it may be applied to apparatus forsheathing cores with material other than rubber. The scope of theinvention is therefore to be limited only by the terms of the followingclaims.

What is claimed is:

1. In an extrusion machine, a member having opposed faces of differentshape and adapted to seat within a cooperating member havingcorrespondingly shaped inner surfaces, the first mentioned member beingprovided with a bore connecting said faces, and a pair of die membersslidably mounted within said bore a d a p d. to

be pressed against said surfaces by the pressure of the material beingextruded.

2. In an extrusion head for applying a coating of insulating materialupon a core, a head block, a second or die holding block mounted withinsaid head block and having a cylindrical opening therein, a core tubeholder removably mounted in one end of the cylindrical opening of thedie holding block, an extrusion die removably mounted in the other endof the cylindrical opening in the die holding block, and a stop oraligning plate mounted within the cylindrical opening for preventing theimproper assembly of said die and said core tube holder in thecylindrical opening of said die holding block.

3. In an extrusion head for applying a coating of insulating materialupon a core, a die holding block having two fiat faces and a tereteface, a head block having one aperture therein arranged to engage 'saidthree faces of the die holding block, and a second aperture therein toprovide communicatiin between one of the flat faces on said die holdingblock through said head block, said die holding block having acylindrical bore therein, a core tube holder removably mounted in oneend of the cylindrical bore in the die hold- -ing block, and anextrusion die removably mounted in'the other end of the cylindrical boreof the die holding block.

4. In an extrusion head for applying a common coating of insulatingmaterial upon a plurality of cores, a head block, a second or dieholding block removably mounted within said head block and having acylindrical bore therein, a plurality of core tubes, a holder for saidcore tubes removably mounted in one end of the cylindrical bore of thedie holding block, an extrusion die having an opening corresponding tothe ultimate configuration of the outer surface of the covering andremovably mounted in the other end of the cylindrical bore of the dieholding block, and a stop or aligning plate mounted within thecylindrical bore to insure proper alignment between said core tubes andthe opening in said extrusion die.

5. In an extrusion head for applying a coating of insulating materialupon a core, a head block having a fiat inner face and an openingextending from said face through said block, a second or die holdingblock having a fiat outer face and a cylindrical opening extendingtherefrom through said die holding block,- an extrusion die removablymounted in the cylindrical opening in said die holding block, said headblock and said die holding block arranged to assemble the die holdingblock in position in the head block by moving the die holding blockperpendicular to the cylindrical opening therein whereby the face ofsaid die holding block is in contact with the face of said head block.

6. In an apparatus for applying a plastic covering material underpressure to a core, a sealed chamber adapted to receive the coveredcore, and a mechanism comprising a floating die, a head block adapted toreceive said die by movement of said die in a direction transverse tothe aperture in the die, and having an apertured wall between said dieand said sealed chamber, means for applying pressure to the plasticcovering material to force it through the die, and means adapted tocooperate with the die to form a seal whereby said die is yieldinglyurged against the wall by the pressure of the covering material.

7. In an apparatus for applying a covering material under pressure to acore, an elongated an apertured wall between said die and said closedchamber, means for applying pressure to the plastic covering material toforce it through the die, and means adapted to cooperate with said dieon one side of the wall to form a seal whereby said die is yieldinglyurged toward said side by the pressure of the covering material.

8. In an apparatus for applying covering material under pressure to acore, a sealed chamber for receiving the core, and a mechanismcomprising a die, a head block adapted to receive said die by movementof said die in a direction transverse to the aperture in the die, andhaving an apertured wall between said die and'saidsealed chamber, meansfor applying pressure to the plastic covering material to force itthrough the die, said die movable with respect to the chamber and urgedagainst the wall by the pressure of the covering material and a gasketinterposed between said die and said wall to provide a seal between thedie and the chamber.

9. In an apparatus for applying covering material under pressure to acore, a chamber havinganopeningiorreceivingthecoreianda mechanismcomprising an apertured member. a head block adapted'to receive saidapertured member by movement thereoi in a direction transverse to theaperture in the die; and having an apertured wall between said aperturedmember and said chamber, means for applying pressure to said coveringmaterial to force it through the apertured member, said apertured membercommunicating with the chamber through the aperture in the wall andmovable with respect thereto and having a yielding connection as saidmember is urged against the wall by the pressure of the coveringmaterial to provide a seal between the member and the chamber.

10. In an apparatus for extruding plastic covering material upon a core,a chamber having an opening for receiving the core, and a mechanismcomprising an apertured block communicating with the chamber, a dieholder having opposed faces of different shape mounted within the blockand having an aperture communicating with the chamber through the block,an extrusion die slidable within the aperture of the die holder andyieldingly urged toward the chamber by the pressure of the materialbeing extruded, to thereby cooperate with the block to provide a sealtor the chamber.

GEORGE L. CHERRY.

Ill

